Use of GIS and other computer methods - Natural England

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Use of GIS and other computer methods - Natural England

LandscapeCharacterAssessmentGuidance for England and ScotlandTOPIC PAPER 4:Use of Geographical InformationSystems and other computermethodsAn introduction to the use of GIS and other computermethods in Landscape Character Assessment includingexamples of good practice and case studies.


Topic paper 4Use of Geographical Information Systems and other computer methodsINTRODUCTION1. Central to Landscape Character Assessment (LCA) is the analysis of relationships between different landscapeelements, such as geology or settlement pattern, in order to classify and describe the landscape. Many landscapeelements are represented by spatial data, whether in digital form or on a paper map.A Geographical InformationSystem (GIS) is a computer system that facilitates the process of storage, analysis and presentation of spatial data [1]and is therefore particularly suited to LCA.2. Geographical Information Systems and other computer methods can facilitate all stages of a LandscapeCharacter Assessment. Investment in technology for LCA will result in a better end product that can be made availableto a wide range of users.The use of GIS will ensure that whatever the current purpose of the LCA, the data willbe in a readily accessible form for a range of potential new uses in the future. Digital information stored in a GIS canbe the principal output of a project, taking the place of a paper report. Unlike a paper report, a GIS database is aflexible, usable and updatable resource.3. Data gathered during LCA field survey can be compiled in a systematic manner, so that it can be stored in aGIS. Digital images of the landscape can be combined with the categorical and descriptive information to give a richdatabase of landscape information.This information can then be used as a resource to aid understanding landscapepatterns and to support landscape planning decisions.4. A GIS provides powerful tools for visualising, presenting and disseminating the results of Landscape CharacterAssessment.The outputs of a GIS can include spatial datasets, online interactive maps, 3D visualisations and papermaps.These different outputs can be made available to a wide range of users to realise the full potential of the LCA.5. The data stored in a GIS can be accessed and manipulated interactively. Hence this data can serve as a test bedfor studying landscape processes, or for analysing the results of trends, or for anticipating the possible results ofplanning decisions [2].6. This paper begins with an overview of important GIS concepts, before describing the role that GIS and othercomputer methods can play during the completion of a Landscape Character Assessment.GIS - BASIC CONCEPTSDefinition of GIS7. A GIS is used for handling map-based information.The information is typically represented as several differentlayers where each layer holds data about a particular kind of feature.A more formal definition of a GIS is a computersystem for capturing, storing, checking, integrating, manipulating, analysing and displaying data related to positions onthe earth's surface [3].A GIS can also be thought of as a decision support tool for tackling spatial problems.GIS Software8. GIS software is a set of programs that carry out geographic processing functions.A wide range of softwarepackages are available, ranging from simple data viewers to desktop GIS and enterprise-wide systems.To ensure thatany chosen GIS software will be suitable for the purposes of the Landscape Character Assessment, the advice ofother GIS users should be sought. It is particularly important to obtain GIS software that permits easy import andexport of data, to facilitate interaction with other GIS users.GIS People9. One of the most important aspects of a GIS is the skill and understanding of the staff using the system [1].Investment in staff training will result in a higher quality LCA and GIS, increasing the decision making capabilities ofthe organisation. GIS training courses are available from private training providers, colleges and universities and viadistance learning over the internet.1


Topic paper 4Use of Geographical Information Systems and other computer methodsGeographic Data10. Geographic data represents landscape elements on the surface of the earth.The format, level of detail andaccuracy of the data will affect this representation. Data can be stored in different formats, with each format beingsuited to particular applications and methods of data capture.11. Raster data is a geographic representation of the world as an array of equally sized pixels, usually square pixels.The pixels are arranged in rows and columns and each pixel is referenced by its geographic location. Examples ofraster data include aerial photography, scanned images or Ordnance Survey 1:50,000 Scale Colour Raster. Raster datais commonly used as a base to other data. Using GIS the pixels can be analysed as they represent a value at ageographic location.12. Vector data represents each individual feature by a point, a line or a polygon.The geographic representation of afeature is linked to a record in a table containing attribute information.Archaeological finds or species records areexamples of point data. Line data includes field boundaries, roads or watercourses. Polygons are used to representcharacter areas, parishes or woodlands.13. Attribute information can be recorded for map features and stored in a data table. Each unique feature has itsown row in this table with numerous columns (or attributes). Each attribute is assigned a data type which defines thedata that can be stored. Data types include text strings, numbers, true/false or date.Co-ordinate systems14. A projection is a mathematical transformation that allows positions on the earth's curved surface to be representedon a flat plane [4].A co-ordinate system is a reference system that identifies the location of a point in space.It is important to ensure that all of the datasets in the GIS store locations in the same projected co-ordinate system.For UK-based projects the Ordnance Survey National Grid is commonly used and most datasets will be supplied inthis projected co-ordinate system.Metadata15. Metadata is the technical word for 'data about data'. It is the term used to describe the summary informationor characteristics of a dataset. Metadata can be used to identify suitable datasets to be used for a LandscapeCharacter Assessment. Metadata should include the title and description of the dataset, an abstract detailing reasonsfor the data collection, when the dataset was created and updated, originator and data supplier and the geographicalextent.All metadata should conform to the latest metadata standards.The current standard is the NationalGeospatial Data Framework (NGDF) standard [5].A new international metadata standard (ISO 19115) is due to bepublished in 2003.DEFINING THE SCOPE16. The scope of a GIS will reflect the scope of the LCA and must be defined at the outset. In common with apaper-based LCA, it is essential to define data requirements and to follow a focussed approach to data gathering tomeet the specific requirements of the assessment.The scoping stage will also guide the design of the GIS database. Itis advisable to gain input from an expert with experience in database design to ensure that data is stored correctlyand efficiently.17. The design of the GIS will depend on the purpose of the assessment and how it is to be used.This will be thekey factor in deciding the type of data to collect. Having decided what data is required it is also critical to scope:• the extent of digital data available for the project;• existence of other (hard copy) data that can be digitised and form part of the GIS, for example paper maps ofarchaeological sites or habitat survey information;• the need for additional work to create new datasets typically, for example, information on cultural landscapefactors including field patterns or settlement typology may require original research and new mapping.18. Table 1 provides a summary of the range of typical sources of digital data for a Landscape Character2


Topic paper 4Use of Geographical Information Systems and other computer methodsAssessment.This table provides some examples of each data type and is an expansion of Box 4.1 'sources of informationfor desk top study' from Landscape Character Assessment Guidance for England and Scotland. It is importantto consider any copyright restrictions when selecting datasets at the outset of a project.This is particularly importantif the LCA GIS will eventually be published online.19. Many local authorities hold GIS data, although there will be issues with data accuracy, data formats and consistencywhen working across local authority boundaries. Certain datasets are available to be downloaded fromwebsites, for example English Nature SSSI boundaries.20. Where digital data is not readily available - such as cultural features or settlement pattern - it may be possibleto create additional datasets through further research/map analysis. However, the resource requirements to undertakethis additional work are often considerable and costs will need to be built into the project at the outset.Whereappropriate any new datasets should be referenced to the national mapping base OS MasterMap.21. There are a number of government sponsored web-based initiatives that can provide information about sourcesof GIS data. GIgateway (Geographical Information Gateway) is a web service aimed at increasing awareness andaccess to geographical information in the UK (www.GIgateway.org.uk). MAGIC (Multi-Agency GeographicInformation for the Countryside) is an online resource offering rural and countryside information from a range ofpublic-sector partner organisations, bringing together definitive rural designation boundaries and information aboutrural land-based schemes (www.magic.gov.uk).Table 1: Data sourcesData Source NotesTopographic map baseAerial photographyGeologyHistoric LandscapeCharacterisationLandform / TopographyHydrologySoilsVegetation/Landcover 2000Ordnance Survey (OS) andother data suppliersVariousBritish Geological SurveyLocal Authorities, EnglishHeritage, Historic Scotland,The Royal Commission onthe Ancient andHistoric Monuments ofScotland (RCAHMS)OS and other datasuppliersEnvironment Agency, ScottishNatural Heritage, SEPANational Soil ResourcesInstitute, Macauly Land UseResearch Institute (MLURI)Landcover Map 2000MLURISEERAD (June census)DEFRA June Census DataVector data at 1:1,250 or 1:2,500(Landline, MasterMap) and rasterdata at 1:10,000, 1:25,000,1:50,000Complete coverage available forEngland and Wales. Full Scotlandcoverage available by 2005.Vector data at various scalesVector data Landform Panorama(10m) and Landform Profile (5m)River catchment boundaries,rivers etcCentre for Ecology andHydrology3


Topic paper 4Use of Geographical Information Systems and other computer methodsTrees / WoodlandAgricultural LandClassificationHabitat surveysHistoric MonumentsNature ConservationDesignationsLandscape CharacterisationInitiatives:Countryside Character AreasNational Landscape Typology(Countryside CharacterDatabase)ForestryCommissionEnglish Nature andScottish Natural HeritageDEFRAMLURILocal Authorities, BiologicalRecord Centres, English Nature,Scottish Natural HeritageEnglish Heritage,RCAHMSEnglish NatureScottish Natural HeritageLocal AuthoritiesCountryside Agency and ScottishNatural HeritageWoodland inventory data fromForestry CommissionAncient Woodlands data fromEnglish Nature and ScottishNatural HeritagePhase 1 Habitat SurveyIncludes Scheduled AncientMonuments, Historic Parks andGardens, Historic BattlefieldsDesignation data available fromEnglish Nature website andScottish Natural HeritageLocal designations fromLocal AuthoritiesContact for further details.Typology data for Englandrequires the signing of a licenseagreement. Some restrictions onsupply of data, depending onnature of use.Scale22. The scale at which GIS data is captured is a critical factor in the use of GIS for decision-making.The scale ofdata collection must be appropriate to the project purpose and its ultimate use.As described in the main LCAguidance, the scale must be agreed at the outset and used consistently throughout the project. For example, a strategiccounty scale assessment may be completed at 1:50,000, or a more detailed townscape assessment or appraisal ofdevelopment options at 1:10,000.23. Although GIS provides the ability to zoom in/out and view data at any scale, it is essential to keep in mind thescale at which it was captured. Datasets captured at 1:250,000 for example are not accurate when displayed at1:50,000. Due to limited data availability, it is often necessary to interpret small-scale data at larger scales duringLCA. If the scale and method of data capture is not clearly understood then consequent decisions made using thedata may be severely misguided.This is particularly important to note when dealing with boundaries.Recording Unit24. When building a GIS to store information about the landscape, it is important to define a consistent recordingunit. Each unit should have a unique reference code for identification. Information describing each recording unit canthen be stored in the database, indexed by the unique code. Landscape information is often stored linked to polygonrecording units.The size of the polygons will depend upon the scale of the assessment and of the landscape beingstudied. Box 1 describes The Living Landscapes Project approach to using polygon recording units.4


Topic paper 4Use of Geographical Information Systems and other computer methodsBox 1: Landscape Description UnitsThe Living Landscapes Project has developed a structured, GIS-based framework for describing and analysing thecountryside [6].This framework operates at different levels of spatial resolution, ranging from the regional (Level1 - 1:250,000), through the county/district (Level 2 - 1:50,000), down to the individual site (1:10,000).TheCountryside Agency in conjunction with The Living Landscapes Project has produced a GIS based regional(1:250,000) landscape character framework and associated database for England.This regional framework hasbeen used to define a Draft National Landscape Typology [7].The draft typology has been devised by theCountryside Agency in collaboration with English Nature and English Heritage.The Living Landscapes Project isworking with local authorities across England to develop a more detailed (Level 2) landscape character framework.The fundamental building block of the hierarchy is theLandscape Description Unit (LDU). LDUs are distinct andrelatively homogenous units of land.The boundaries of eachLDU are defined by analysis of definitive attributes.Thedefinitive attributes are derived from published map-baseddata.The four definitive attributes at Level 1 (regional) arephysiography, ground type, land cover and cultural pattern.At Level 2 (county/district), each of the attributes is splitinto two parts, giving a total of eight definitive attributes.Thisallows for a finer grain of mapping, whilst retaining thehierarchical structure of the spatial framework.Thus an LDUdefined as 'soft rock low hills' at the regional scale might besub-divided into three LDUs at the county/district scaledefined as 'scarp edge', 'plateau summit' and 'dip slopevalleys'.The relationship between the Level 1 and Level 2definitive attributes is summarised in Table 2.Natural CulturalRegionalLevel 1 (1:250,000)PhysiographyGround typeSettlementLandcoverCounty/DistrictLevel 2 (1:50,000)LandformGeology (structure)Geology (rock type)SoilsSettlementFarm type (structure)Farm type (cover)Tree coverTable 2: Summary of LDU definitiveattributesThe process of LDU mapping involves a step-by-step procedureof data acquisition, processing and synthesis to produce a series of character based GIS layersincorporating the key factors that contribute to landscape character.The natural dimension of the landscape ismapped first (Figure 1).The attributes of landform, geology and soils have boundaries which are derived fromexisting published maps. Cultural datasets are used to describe the cultural aspect of the landscape and to subdivideLDUs where appropriate.The definition of discrete LDUs provides a meaningful and structured spatial framework for gathering additionaldescriptive information about the landscape. LDUs represent areas of common character to be verified anddescribed during Landscape Character Assessment.At the field survey stage, the boundaries of the LDUs can bechecked and information can be gathered to describe aspects, such as scale, form and enclosure. LDUs can thenbe classified according to shared characteristics to define Landscape Character Types. If necessary, large LDUscan be subdivided to define Landscape Character Areas.The LDU framework has been used for a wide range of applications including habitat creation targeting,woodland strategy, housing allocation and assessment of the impact of highway development.5


Topic paper 4Use of Geographical Information Systems and other computer methodsFigure 1:Simplified geologybase withcontour overlay -physiographicunits shown asbold lines.DESK STUDY25. The aim of this stage of the assessment is to divide the landscape into areas of common character.A valuableuse of GIS is for the collation and analysis of information gathered as part of the desk study stage of a LandscapeCharacter Assessment. GIS can be used to build up an information base by collating existing layers of digital data ordigitising new layers.26. The value of using GIS at this stage is that it allows complex layers of data to be overlaid and viewed on an OSbase.The spatial relationships between datasets can then be analysed. It is important to remember that there will beassumptions, errors and inconsistency in many of the base datasets used for Landscape Character Assessment.Limitations in datasets should be acknowledged and accounted for and any assumptions made during the desk studyshould be recorded.27. GIS can be used at a range of different levels to aid the draft characterisation:• GIS can be used to view datasets and visually assess spatial distribution and correlations, which form the basisfor defining areas of common character.This process has traditionally been achieved by overlaying a number ofacetate sheets. Undertaking the same process on GIS not only overcomes the problems associated with enlarging/reducingsource maps at different scales, but it also allows for greater scope in the analysis of the data.The6


Topic paper 4Use of Geographical Information Systems and other computer methodsfull potential of GIS continues to be constrained, however, by difficulties associated with availability of digitaldata and access to it. Several of the key baseline datasets are often too costly to purchase or simply notavailable in a digital format(e. g. settlement).• A particularly useful application at thisstage is the viewing of informationusing a 3D contour model, such as oneshowing the relationships betweenlandform and geology (Figure 2) orlandform and land cover.This can aidthe understanding of interrelationshipsbetween landscape elements.• GIS can be used to interpret andanalyse datasets in relation to eachother, for example by setting parameterssuch as "show all areas over200m elevation with >50 % woodlandcover". Clearly, professional judgementis needed to define sensible thresholdsand critical values for suchanalysis.• At a more sophisticated level a GIScan be used as a tool to carry outspatial analysis. Such analysis can beused to combine datasets and defineareas with similar characteristics.This technique has great potential to aid determination of areas of commoncharacter, but will require considerable technical expertise.28. The output of this work will be a draft map of areas of common character for field testing.The use of GIS todevelop the draft map in digital format has the advantage that boundaries can be easily refined and amended as thestudy progresses.FIELD SURVEYFigure 2:Visualising data in 3D can assist in the understanding ofa landscape. In this example looking south down the Thames Valleyover Oxford, the 1:50,000 OS map base, geology, rivers and majorroads are all draped over a 3D model constructed from contourdata.The relationship of the settlement pattern of Oxford to thelandform is evident with Oxford city centre situated on raisedriver terrace deposits at the confluence of the Thames andCherwell.Hand Held Computers and Field Record Sheets29. GIS can be invaluable as part of the field survey, notably through the use of hand held computers.This approachmakes baseline information more portable for easier use in the field, allowing the interrogation of underlying datasetssuch as geology.The use of portable computers allows field survey information to be recorded directly into the GISdatabase, including any modifications to draft landscape boundaries. It is important to verify the information andcheck for errors.30. It is advisable to use a weatherproof computer that is designed for use in the field.A standard laptop computermay cause practical difficulties during field survey, especially in wet weather or in bright sunshine. It is essential thatfield survey data is backed up frequently, either via external disks or through a mobile internet connection.31. If it is not possible to use handheld computers then a tailored field record sheet should be used to recordobservations on the landscape in a systematic format.The field survey sheet should be designed to maximise theconsistency of recorded information. Field sheets must be clearly linked to a recording unit or location with a uniqueidentifier. Pick lists of pre-defined terms will help to ensure that a consistent dataset of categorical data is captured.7


Topic paper 4Use of Geographical Information Systems and other computer methodsThere should be sufficient room on the survey sheet to accommodate written comments and field observations,which can also be stored in a GIS. Box 2 describes how this approach to gathering landscape information was usedin Derbyshire.Photography32. Photographic images can form an important part of a LCA GIS, recording visual characteristics of the landscape.Digital images for the GIS database can be either taken using a digital camera or scanned from photographs. Imagescan then be stored in the GIS and linked to point features that can be displayed as arrows on a GIS map interface.33. Photographs collected during a LCA can be used to construct visualisations of the present landscape andscenarios for future landscapes. Even if landscape visualisations are not an immediate intended output of an LCA, thecollection of suitable information and images will make this possible in the future and will add value to the datagathered in the field without significant increases in cost. Photographs that record individual landscape features willbe useful for constructing more realistic landscape visualisations. Features recorded could include tree species orbuilding materials and images should be composed to allow features to be 'cut out' using graphics software.34. All photographs should be assigned a unique identifying code together with a grid reference, bearing, date andnotes describing the image. In addition, the following information should be gathered about each photograph to aidthe construction of landscape visualisations: notes to allow a future visitor to locate themselves at the same spot, thetime of the photograph and weather conditions. It is also important to record the focal length and field of view ofthe camera lens. For a fixed lens this information would only need to be recorded once.Global Positioning System35. Global Positioning System (GPS) is a satellite-based positioning and navigation system owned and operated bythe US Department of Defence. GPS can give an instantaneous, real-time position to within approximately 20m usinga handheld receiver. GPS should be used in conjunction with a paper map or field GIS for positioning and plotting ofdata. GPS is particularly useful for recording viewpoints, photographs or modifying draft boundaries, particularly inopen landscapes with few landscape features that can be used to locate a position on a map.The use of GPS requiresan initial investment in the technology and training and it should always be complemented by good map reading skills.It will be necessary to convert GPS data in latitude and longitude format to Ordnance Survey National Grid eastingsand northings.The National GPS Network website (www.gps.gov.uk) contains further information about GPS anddata conversion.Box 2: Derbyshire Landscape Character AssessmentDerbyshire Landscape Character Assessment [8] has described and classified the landscapes of Derbyshirethrough detailed desk study and field survey. During the desk study stage of the LCA, some 500 LandscapeDescription Units (LDUs) were defined, which were divided into nearly 2000 Land Cover Parcels (LCPs). LDUsand LCPs have been digitized over Ordnance Survey 1:25,000 Raster data. Field survey was used to verify theboundaries of the units and to record attribute information for each LDU and LCP, using a structured surveysheet.Almost 100 attributes have been recorded for each LCP and nearly 30 for each LDU, together withdescriptive textual information.All of the information gathered has been stored using MapInfo GIS and MicrosoftAccess.Data includes:GeologyLandformSoilsLand useSettlement patternTree coverBuilding styleBoundary type/speciesImpact of mineral extraction8


Topic paper 4Use of Geographical Information Systems and other computer methods39 Landscape Character Types were defined through a combination of GIS analysis and interpretation of thelandscape information gathered in the field. GIS was used as an aid to the preparation of descriptions of eachLandscape Character Type. GIS was used to produce working maps and presentation quality maps included inthe draft LCA.The GIS has been extended to include the results of Derbyshire Historic Landscape Characterisation and digitalaerial photography.The inclusion of the field survey photographic record in the GIS has also been explored(Figure 3).The data provides a resource for Landscape Character information to inform strategic and developmentcontrol planning.The database is also being used to develop a woodland strategy and to focus countyBiodiversity Action Plan targets.21Photo 1 Photo 2Figure 3. Maps showing Landscape Character Types and the impact of mineral extraction in North-EastDerbyshire. Photographs 1 and 2 show the contrasting impacts of mineral extraction in the DerbyshireCoalfield and are linked to the GIS database as shown in the map on the right above.9


Topic paper 4Use of Geographical Information Systems and other computer methodsCLASSIFICATION AND DESCRIPTIONClassification36. Characterisation is concerned with the process of dividing the landscape into areas of distinct, recognisable andconsistent character. Classification involves grouping areas of similar character together. Classification can be carriedout manually or informed by statistical analysis of landscape data. GIS can be used to assist manual classification, or tostore and process landscape data for statistical analysis.37. Manual classification involves the combined analysis of the many layers of data gathered during the study. GIScan be used to map different layers of information to permit rapid visual comparison between layers. GIS can also beused to produce maps combining information from different layers, for example a map of tree cover character thatshows the extent of woodland and the density of boundary trees. Exploring the relationship between layers of datawill help users to identify patterns in the landscape and to define Landscape Character Types and Areas.38. Computer classification involves the use of statistical techniques to identify relationships between layers of data.The success of a computer classification is dependent on the type and quality of input data and on the appropriatenessof the classification technique that is used.While statistical classification can be a very useful tool for examiningpatterns in complicated data, considerable care must be taken during data processing and in the interpretation of theresults.39. Any data that has been gathered during the desk study and field survey can be used for classification, providedthat it has been gathered and stored in a consistent and logical format. For example, if a category for dominant buildingmaterial has been allocated to each recording unit then the GIS can be used to produce a map of dominantbuilding material across the landscape.This map can be used to inform manual classification.Alternatively, thedominant building material could act as an input variable for statistical analysis.40. Landscape Character Types and Landscape Character Areas are a key output of a LCA.They can be defined bymanual techniques or through the use of computer classification methods. Importantly, they should incorporate theviews of stakeholders, to ensure that they are widely accepted and understood. GIS can be useful for engaging stakeholdersby facilitating the production of high quality paper maps of draft Landscape Character Types and Areas fordiscussion. Stakeholders can use GIS to display, understand and comment upon draft Landscape Character Types andAreas, at workshops or over the Internet using online interactive maps. Stakeholders already using a GIS can besupplied with draft data for comparison with other data sets.Description41. GIS can be used to explore patterns in data collected during the LCA, as an aid to producing written descriptions.It is often useful to use queries to select manageable subsets of the database. Sorting the data using differentcolumns can aid the identification of patterns and relationships in the data.42. While GIS can help to identify patterns in the data, it is important that written descriptions of LandscapeCharacter Types and Areas consider the relationship between different landscape elements. Descriptions should alsoinclude information gathered during field survey and the views of stakeholders, as described in the main LCAGuidance.43. GIS can also be used to analyse landscape data together with additional datasets to add detail to the descriptions.For example, a digital Phase 1 Habitat Survey could be used to provide information about characteristic wildlifehabitats in a type or area.A Sites and Monuments Record database could be used to identify landscapes associatedwith particular cultural heritage features.10


Topic paper 4Use of Geographical Information Systems and other computer methodsDISSEMINATIONDistributing data44. GIS datasets produced during a Landscape Character Assessment can be made available to a wide range ofstakeholders.The datasets can be made available for download from the Internet, on a geographical feature server orincluded on a CD with a project report. Box 3 describes the GIS dataset that is available from Scottish NaturalHeritage. It is important to consider copyright issues when making data available to third parties.Box 3: GIS Dataset of Landscape Character Assessment Information in ScotlandFollowing the completion of the national programme of Landscape Character Assessment in Scotland, ScottishNatural Heritage developed a national dataset compiled from the 29 Landscape Character Assessments (LCAs).This exercise provided several key attributes for each landscape unit:• key words describing the key characteristics and features of the 366 landscape character types (LCTs)identified;• a "pen portrait" text description; and• a standard list of "Pressures for Change" in the landscape.These attributes have been linked to a national GIS containing the 366 LCTs derived from the c. 3900 landscapeunits identified in the LCA reports, summarising information about the landscape of Scotland in a readily accessibleformat.As part of the exercise, the initial 366 Level 1 types were grouped on the basis of similarities in theirkey characteristics, into 106 Level 2 types and subsequently into 52 Level 3 types [9].In 2002 the data was updated to correct for spatial and attribute errors in order to create a more robustdataset.This involved registration of all coastal boundaries to the OS 1:25,000 coastal dataset and the realignmentof internal (land) polygon boundaries to account for this. SNH Landscape advisors were involved in thisupdating process, assisting with the verification and re-drawing of some LCT boundaries. It is envisaged thatsome spatial (and to some degree attribute) errors within the data may remain due to the original data capturemethodology, and SNH will continue to review and update this valuable dataset.This dataset will be used in a range of large scale land use planning and management work, for example, inmapping landscape sensitivity to wind energy development. It will also help to provide a better understanding ofthe landscape resource in Scotland.45. To allow users to interpret and use the data correctly, care must be taken to ensure that sufficient metadata issupplied with any LCA datasets. Metadata should follow the NGDF Metadata standards (www.GIgateway.org.uk). It isparticularly important that categories and technical terms used in the database are clearly defined in the metadata. Itis also vital that the purpose and scale of the study are described and that contact details for the owner of thedataset are clearly identified. Data such as version number, date and author will assist with version control.Online interactive maps46. Recent advances in GIS and Internet technology allow the dissemination of the results of a LandscapeCharacter Assessment via online interactive maps. Landscape Character Types and Areas can be linked to text andimages, allowing users to explore the Landscape Character Assessment interactively. Interactive maps should be welldesigned and easy to use. Users must be provided with sufficient metadata, background information and helpresources to enable them to interpret the data.11


Topic paper 4Use of Geographical Information Systems and other computer methods47. Many government bodies are now making their spatial data available through corporate interactive maps.Datasets produced as part of a Landscape Character Assessment can be an engaging addition to such interactivemaps. Landscape character information can provide a useful landscape context for other information.A LandscapeCharacter Assessment database can also provide information about particular landscape elements such as landform,tree cover or building materials.Visualisation48. Advances in technology have opened up the possibility of using 3D models to visualise the landscape.Visualisation techniques can be used to illustrate possible developments and landscape scenarios, for example in theproduction of Local Development Frameworks.A LCA GIS database can provide valuable information to be used forvisualization, including digital images and data describing building materials or hedgerow species.49. Landscape visualisation depends upon computer graphics, 3D modelling and GIS software. It requires attentionto the specific challenges of modelling landscape elements. Landscape models can span a broad range of styles,presentation media, and ranges of realism from "photographic" to impressionistic and highly abstract. Choosing andusing the right level of abstraction, and the appropriate medium for presentation and communication, requires bothtechnical knowledge of the media and professional design judgement [10].Paper map production50. Modern GIS and digital print technology permit the production of high quality paper maps. Sufficient careshould be taken in the choice of colours, shading and layout to ensure that the resulting maps are clear and conveythe correct information. It is important to remember that colours assigned to map features can appear very differentlyon various screens and printers. It is advisable to obtain input from a professional cartographer or graphicdesigner to ensure a high standard of map production.51. When producing maps for a Landscape Character Assessment, it is important to include topographic maps of asuitable level of detail, to allow users of the map to interpret the data. Background mapping should include roads,watercourses, railways and settlements to allow users to orient themselves on the map.The production of large scalemaps that clearly show buildings and field boundaries will help to engage local people.MAKING JUDGEMENTS52. A dataset of Landscape Character Types and Areas captures spatial variation in natural, cultural and visualelements in the landscape.The integrative nature of a LCA database makes it well suited to be used as a frameworkfor analysing other datasets and for holistic landscape planning.Easy querying53. A key benefit of using GIS is the ease with which it is possible to query the LCA data for a particular purpose,such as targeting resources or carrying out more detailed survey work. Data gathered during the desk study or fieldsurvey can be queried using GIS and the results displayed as maps or in a table. For example, a project to conserveand enhance field boundaries could be tailored to the characteristic boundary types of each particular landscape.Similarly, a project to reduce the landscape impact of mineral extraction could be targeted to areas where a highimpact has been recorded in the field.A project to survey the distribution and extent of a particular wildlife habitatcould be limited to landscapes that are known to be associated with that habitat.Combination with other datasets54. Analysis of the LCA data and the addition of other datasets can be used to study patterns in the landscape,produce spatial landscape strategies and to target resources. GIS can be used to reclassify landscapes using otherdatasets for further study of the landscape or for targeting resources. For example, landscapes could be classifiedaccording to the presence of rare or important species, using biological records.This classification could then be usedto target landscape-level conservation resources.12


Topic paper 4Use of Geographical Information Systems and other computer methodsBox 4:The County Durham Landscape AssessmentThe County Durham Landscape Assessment [12] is based on an integrated GIS database which subdivides thelandscape of the county into around 5,800 mapping units. For each of these units information is recorded on arange of attributes that influence the character of the landscape.The database evolved as new data became availableduring the study.Existing GIS datasets - including Geology (solid & drift), Soils, Land use (satellite data),Woodlands,AncientWoodlands, Historic Parklands, Settlements, Enclosure Awards, Mineral Workings & Reclaimed land - were usedto create broad mapping units.These units were subdivided and refined manually on the basis of a morphologicalanalysis of field systems and topography.These units were further refined and subdivided using aerial photographyproviding greater detail on land use and tree cover. As new data became available, or as new topics wereexplored, the data was revisited and revised.Attribute fields in the ArcView GIS database include:Geology: SolidGeology: DriftSoilsLandformLand UseField PatternField ScaleBoundary TypeTree CoverWoodland PatternSettlement TypeSettlement PatternOriginsRelics: Bronze Age Settlement &Ritual LandscapesRelics: Medieval Agriculture &SettlementRelics: Mining & IndustryThe database was analysed for patterns of attributes.This process, together with observations in the field, wasused to identify:• Broad landscape types and sub-types• Local landscape types and sub-typesIn the early stages of development the GIS exercise was seen primarily as a tool for landscape classification.As ithas evolved it has increasingly been seen as a useful tool in its own right as baseline data on a wide range oflandscape features and attributes, similar in some respects to a Phase 1 Habitat Survey.While the raw data hasbeen processed to produce landscape types, it remains available as baseline data for other uses. In manyapplications it is more useful than the landscape typology. For any given attribute being considered (e. g treecover, enclosure period, settlement pattern) the baseline data involves less generalisation and therefore hasgreater accuracy than the typology.Current applications of the data-set include:• Developing Landscape Strategies at a range of levels (County, Regional Character Areas, Broad LandscapeTypes, Local Landscape Types).The fine grain mapping units are analysed against the landscape types theybelong to in respect of their condition, their contribution to local distinctiveness, biodiversity, culturalheritage etc in order to arrive at broad strategies for conservation, restoration, enhancement etc.• Landscape sensitivity mapping for a regional Wind Energy Capacity Study.• Landscape sensitivity mapping for the county Waste Local Plan.• Landscape sensitivity/opportunity mapping for a County Woodland Strategy.• Intranet access through ArcIMS for general use in DCC and District Councils (under development).• Extranet access for schools through ArcIMS as an educational resource primarily in Geography (underdevelopment).• Internet access for the public at large combining ArcIMS mapping (under development) and the text basedinformation of the Landscape Assessment and Landscape Strategy on the web.13


Topic paper 4Use of Geographical Information Systems and other computer methodsFuture TrendsA Historic Landscape Character Assessment is proposed for the county in 2003-2004.This will be undertakenusing OS MasterMap, which has only recently become available. It is likely that the CDLA data will be reviewedat the same time to put it into that format and to be integrated with the HLCA data.Figure 4: Screen shot of the County Durham Landscape Character AssessmentGIS database, showing the baseline dataSensitivity and capacity56. The GIS database can be extended by the evaluation stage of a Landscape Character Assessment [11].A structuredand transparent method of analysis should be developed to evaluate the sensitivity of landscapes to change.TheLCA database can be combined with other datasets to evaluate the capacity of the landscape to accommodatechange and development (Box 4). Studies have used GIS to model landscape capacity for wind energy, housing developmentand woodland creation.FUTURE TRENDS57. GIS will become an increasingly common tool for LCA. It will be no more remarkable than the use of wordprocessing and desktop publishing software for the production of a project report.While GIS will be increasingly easyto use and affordable, it is important that its use is backed up by sufficient understanding and training.58. Increased public access to the internet will make online GIS more effective as a means to engage communitieswith LCA. Online GIS can be a live database that is updated as new information and understanding develops. Greatercomputer power and software development will make landscape visualisation a much more widely used technique forengaging stakeholders in landscape planning.14


Topic paper 4Use of Geographical Information Systems and other computer methodsFigure 5: Wind energy development sensitivity analysis for County Durham, carried outusing the Landscape Character Assessment GIS databaseACKNOWLEDGEMENTSThis topic paper has been authored by Jonathan Porter (Countryscape) and Kate Ahern (Land Use Consultants) onbehalf of the Countryside Agency and Scottish Natural Heritage. The authors are grateful for the helpfulcomments and suggestions made by Katy Appleton (University of East Anglia), Nigel Buchan (Scottish NaturalHeritage), Mark Diacono (Diacono Associates), Gary Ellis (Derbyshire County Council), Geoffrey Griffiths (TheUniversity of Reading), Ged Lawson (Durham County Council), Steve Potter (Staffordshire County Council),AllyRood (The Countryside Agency), Steven Warnock (The Living Landscapes Project) and Andy Wharton (TheCountryside Agency).The Countryside Agency would like to thank Countryscape for co-ordinatingthe preparation of this topic paper.Further InformationShare your ideas, experience, knowledge and use of Landscape Character Assessment with others by joining theCountryside Character Network at www.ccnetwork.org.uk. Feedback and continued discussion on this topicpaper and others can be made via the on-line discussion forum.REFERENCES[1] Longley, P. et al (2002) Geographic Information Systems and Science. John Wiley & Sons, Chichester.[2] Burrough, P.A. (1986) Principles of Geographical Information Systems for Land Resources Assessment. ClarendonPress, Oxford.15


Topic paper 4Use of Geographical Information Systems and other computer methods[3] Association for Geographic Information. AGI Online GIS Dictionary. www.agi.org.uk[4] Kennedy, M. & Kopp, S. (2001) Understanding Map Projections. Environmental Systems Research Institute, Inc,Redlands.[5] National Geospatial Data Framework metadata standard. www.GIgateway.org.uk[6] Warnock S. (2002) The Living Landscapes Project Landscape Characterisation Handbook: Level 2. Departmentof Geography,The University of Reading, Reading.[7] Pike,T. (2001) Development of a National Landscape Typology for England. Countryside Character NetworkNewsletter. Issue 6. Countryside Agency/ ERM.[8] Derbyshire County Council (2002) Derbyshire Landscape Character Assessment: Consultation Draft Summer 2002.Derbyshire County Council, Matlock.[9] David Tyldesley and Associates (1998) Final and Method report (contract number BAT/97/98/80). Scottish NaturalHeritage.[10] Ervin, S. M. & Hasbrouck, H. H. Landscape Modeling: Computational Techniques for Landscape Design, Planning andSimulation. McGraw-Hill (Accompanying website www.landscapemodeling.org)[11] Swanwick, C. (Forthcoming) Techniques for Judging Capactity and Sensitivity: Landscape Character Assesment:Guidance for England and Scotland - Topic Paper 6.The Countryside Agency, Cheltenham and Scottish NaturalHeritage, Edinburgh.[12] Sheils Flynn (2002) A Landscape Character Assessment of County Durham. Report to The Countryside Agency withassistance from Durham County Council.The full Landscape Character Assessment: Guidance for England and Scotland and related topic papers can be viewedand downloaded from www.countryside.gov.uk/cci/guidance and www.snh.org.uk/strategy/LCAFree copies of the guidance are also available from:Countryside Agency PublicationsScottish Natural HeritageTel: 0870 1206466 Tel: 0131 446 2400Fax: 0870 1206467 Fax: 0131 446 2405Email: countryside@twoten.press.netEmail: carolyn.dunnett@snh.gov.ukThe map extract used within this publication is reproduced from Ordnance Survey material with the permission of Ordnance Survey on behalf of the Controller of Her Majesty's Stationary Office© Crown copyright. Unauthorised reproduction infringes Crown copyright and may lead to prosecution or civil proceedings. Countryside Agency, GD272434, 2002.16

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